The invention relates to an apparatus for preparing carpets with flattened nap for cleaning and having a brushing and scratching tool provided with a carrier that is moved over the carpet and from which downwardly extend bar-like elements which engage in the carpet nap and serve to loosen it.
Such an apparatus by means of which the nap of a carpet is supposed to be arranged for subsequent cleaning is already known. A brush-like tool with rod-like members is drawn through the carpet nap. This tool is however not intended for use with carpets of different nap lengths. Only longknapped carpets, such as used in residences, and which are not subject to considerable traffic, can be loosened up enough with such a tool that the particles of dirt deposited in the nap can be sucked out. This known device does not permit the cleaning of short-nap carpets with a fine dense nap as are for instance used in sales areas of stores or banks where they are subject to rather considerable dirt and wear along with considerable pedestrian traffic. The relatively widely spaced and thick rod-like elements of the brush tool, which are made of the same material as the plate carrying these elements and which are integral therewith, can in fact not effectively engage in the walked-down fine and dense nap of a low-nap carpet. On one hand the spacing between the rod-like members is too large to insure a complete engagement against all of the nap and on the other hand these rod-like elements, which must have a relatively great elasticity so as to work on the long nap without damaging it, are deflected in every direction when used on walked-down short-nap carpets and do not therefore loosen the dirt therein.
On the application date other brushes were known which had a separate elastically bedded wire bristles. These are hair or wig brushes which are meant to work on human hair and whose wire bristles therefore must be very loosely bedded so that the hair being worked on, which is not being loosened up because of dirt, is not ripped out. Such brushes are in an entirely different field.
Further known arrangements, serving to raise nap before cleaning of carpets and having motor-driven rotating rollers whose peripheries are provided with alternate rigid short and long bars, are only usable for raising a nap with a length of approximately 40 mm. Carpets with such a high nap are exclusively found in private rooms and normally are not dirtied so much that the nap is stuck to the backing. These already known devices with widely spaced rigid rods are not suitable for raising the walked-down and stuck-together nap of carpets which are provided in rooms subjected to heavy pedestrian traffic; since an apparatus with a motordriven roller provided with rigid radially extending rods which serves to comb out the long nap of carpets would when this roller is used for the raising of a low stuck-together nap subject this short nap with a correspondingly great force which would in most cases wear it away since each individual stiff member would transmit the full rotational force of this roller to the nap in a case when this nap as a result of being very dirty offered a correspondingly high resistance to the apparatus.